Duty crimes are severe phenomena of corruption. Investigating and preventing duty crimes are vital responsibilities of the People’s Procuratorates given by the law. Since 18^th National Congress of CPC，the People’s Procuratorates conscientiously implement the decisions and arrangements of the Central Committee，perform their duties strictly in accordance with the law，carry on the principle of “targeting both the tigers and flies”，further diversify the resources of cases，utilize the method of “systemic investigation”，realize the function of unified investigation sufficiently，elaborate the balance mechanism of investigation supervision constantly，strengthen the team of procurators and optimize the environment of enforcement. With the measures above，procuratorates ensure their enforcement of the law to be strict，canonical，civilized and just，investigate a large amount of severe and reciprocal duty crimes with sensational effects in deep，keep the high pressure of the punishment towards corruption，perform as pioneers in the combat against corruption.